Spraying systems

ABSTRACT

Spraying apparatus is provided which employs a porous member through which a liquid is forced and is caused to be disspelled from a surface thereof as a spray or atomized particles. In one form, liquid is forced from a first chamber through a porous wall or plug to the outer surface thereof by applying pressure directly to the liquid and, upon emerging on said outer surface, one or more jets of high velocity gas are directed against said outer surface to lift and atomize the liquid and direct same as a spray into the surrounding atmosphere. In another form, liquid is admitted to a chamber having a porous wall portion and one or more jets of high-velocity gas are directed from the exterior of said chamber through the porous wall portion, into the liquid therein and through a second portion of the wall of the chamber which is also porous. The gas acts to force liquid in the chamber through the second portion of the wall thereof and beyond the chamber as an atomized spray. The apparatus is particularly applicable for atomizing, and in certain instances, vaporizing liquid introduced over a substantially large surface area without the need for precisely machined nozzled devices.

United States Patent Jerome I-l. Lemelson 85 Rector St., Metuchen, NJ. 08840 [72] Inventor I21] Applv No 801,544 [22] Filed Feb. 24, 1969 [45] Patented June 8,1971

[54] SPRAYING SYSTEMS Primary Examiner-M. Henson Wood, .lr. Assistant Examiner-Michael Y. Mar

ABSTRACT: Spraying apparatus is provided which employs a porous member through which a liquid is forced and is caused to be disspelled from a surface thereof as a spray or atomized particles. In one form, liquid is forced from a first chamber through a porous wall or plug to the outer surface thereof by applying pressure directly to the liquid and, upon emerging on said outer surface, one or more jets of high velocity gas are directed against said outer surface to lift and atomize the liquid and direct same as a spray into the surrounding atmosphere.

In another form, liquid is admitted to a chamber having a porous wall portion and one or more jets of high-velocity gas are directed from the exterior of said chamber through the porous wall portion, into the liquid therein and through a second portion of the wall of the chamber which is also porous. The gas acts to force liquid in the chamber through the second portion of the wall thereof and beyond the chamber as an atomized spray. The apparatus is particularly applicable for atomizing, and in certain instances, vaporizing liquid introduced over a substantially large surface area without the need for precisely machined nozzled devices.

PATENT EU JUN 8 ISYI GAS COMPRESSOR FIG.2

I INVENTOR. JEROME H.LEMELSON SPRAYING SYSTEMS SUMMARY OF THE INVENTION This invention relates to apparatus for spraying and atomizing liquids such as chemicals, fuels, water or other liquids required to be dispersed as a fine mist over a substantially large area. The conventional means for spraying liquids involves the use of one or more nozzles which are specially shaped to break up and dispense the liquid as a spray or flow of droplets. Nozzles are generally made of metal and require a multiplicity of machining operations to derive the proper shape which is operative to cause the liquid to be dispensed as a spray or atomized flow pattern. The production of nozzles containing single passageways or orifices or a plurality of same is generally quite costly as they require surface finishing and special contouring. If it is desired to provide a spray pattern over a substantially large area, generally a multiplicity of such nozzles are required and must be individually assembled with one or more conduits and aligned or located so as to effect the desired spray pattern.

It is a primary object of this invention to provide a new and improved spray-producing apparatus and method for spraying liquids.

Another object is to provide an apparatus for spraying liquids from a tubular member having a porous wall, the tubular member serving as a conduit and receptacle for the liquid and the porous wall serving either to permit the controlled flow of the liquid to a surface thereof and/or to break up the liquid nto fine droplets.

Another object is to provide a new and improved spraying apparatus which is relatively low in cost and easily fabricated.

Another object is to provide a spraying apparatus permitting the dispensing of a liquid of a substantially large area without the need for utilizing individual nozzles.

Another object is to provide a spraying apparatus capable of producing a sheetlike spray of finely atomized particles of liquid over a large area by employing a single extrusion.

Another object is to provide new and improved spray heads applicable to the end of pipe and hoses and employing one or more porous members.

Another object is to provide an improved apparatus for spraying liquid introduced through a porous member whereby the life of the porous member is substantially extended.

Another object is to provide an apparatus and method for vaporizing a liquid from a surface ofa porous member.

With the above and such other objects in view as may hereafter more fully appear, the invention consists of novel constructions, combinations and arrangements of parts as will be more fully described and illustrated in the accompanying drawings, and it is to be understood that changes, variations and modifications may be resorted to which fall within the scope of the invention as claimed.

In the drawings:

FIG. I is a partial end view in cross section ofa spraying apparatus employing a porous walled conduit containing a liquid to be spray-dispensed and a second conduit assembled with the first conduit and containing gas and means for directing one or morejets of said gas directly through the porous-walled conduit to dispense liquid therefrom;

FIG. 2 is a partial view in end cross section of a modified form of spraying apparatus employing gas directed against the outer surface of a porous wall of a conduit; FIG. 3 is a schematic diagram employing either of the devices of FIGS. 1 and FIG. 4 is a partial view in side cross section of a spray plug or nozzle employing a porous member and means for directing gas against the outer surface thereof;

FIG. 5 is a side view in cross section of a modified form of porous end plug employing means for flowing liquid through the plug and directing a jet of high'velocity gas therethrough; and

FIG. 6 is an end view in cross section of an extrusion operative to spray liquid therefrom.

There is shown in FIG. I a spraying apparatus 10 composed ofa first conduit 11 which may be an elongated metal, plastic or ceramic extrusion shown in end view and having a top wall 12, a bottom wall I3 and an end wall I4 defining an elongated passageway I5 through which a suitable gas such as air is flowed under pressure. A shelf extension 13 of the bottom wall 13 protrudes from the end wall 14 as shown and mounts an elongated tubular member 17 having a porous sidewall I7 and defining a passageway 18 containing liquid to be dispensed. The notation I9 refers to welding or adhesive bonding material disposed between the upper surface of the shelf 13' and the bottom of tubular member I7 for retaining the two in assembly. Other means such as fasteners or specially shaping the shelf I3 may also be employed to assemble the tubular member I7 with the member II.

A plurality of holes 16 are provided in the end wall 14 in direct alignment with the tubular member 17. When the gas located within the conduit 15 of member 11 is highly pressurized, it will escape through the holes I6 and be directed as separate jets of gas through the portion of the porous wall 17' facing wall 14. If the velocity of the gas jets directed against wall 17 is great enough, the gas will be forced into the chamber 18, through the liquid therein and will carry liquid through the opposite portion of the wall 17' and dispense same therebeyond as fine droplets or an atomized mist. If the holes 16 extend along the length of member 11, said spray or mist will extend for the length of member 17 and be dispensed as a sheetlike formation of fine droplets over a substantially large area.

In FIG. 2, a spraying device 20 is composed of an elongated extrusion having a bottom wall 21, a top wall 22 and a center wall 23 separating the top and bottom walls so as to provide two separate chambers, an upper chamber 28 and a lower chamber 29. The end wall 25 of the chamber 28 terminates before the end wall 27 of chamber 29. Extending between the end wall 25 and end wall 27 is a porous wall portion 30 made of a strip of porous metal, plastic or ceramic which is either formed in situ during the formation of the extrusion 24. Tubular wall portion 30 may comprise a perforated portion of the extrusion or a sintered plastic, ceramic or composite material.

A plurality of holes 26 extending through the end wall portion 25 are directed so as to direct high-velocity streams of gas under pressure within chamber 28 above and against the upper surface of porous wall portion 30. By properly pressurizing the liquid in chamber 29, it will be caused to flow to the upper surface of porous wall portion 30 and form a film thereon which film is rapidly removed by the high-velocity jets of gas directed through the openings 26 which extend along the end of the end wall 25 at spaced intervals. The result is a spray of droplets or atomized particles of liquid mixed with the gas ejected from chamber 28 and flowed downstream of the end wall 27 as illustrated.

In FIG. 3 is shown a spraying system employing sprayproducing components of the types shown either in FIG. 1 or 2. The system 32 employs a compressor 39 such as an air compressor for directing gas under pressure through a pipe 38 which is connected to an elongated tube or pipe 11 by means of a coupling 37. Supported immediately adjacent to the pipe 11 is an elongated duct 17a having all or a portion of the wall thereof made of a porous, liquid-conducting material as described. A plurality of spaced apart holes 16 provided in the wall of tube 11' are directed so as to direct respective streams of gas either completely through the porous conduit 17a as shown in FIG. 1 or directly over the outer surface of the porous wall thereof as shown in FIG. 2. A pump 36 is provided to pressurize and flow liquid through a conduit 35 extending to the porous walled member 17a under suitable pressure to perform either of the spraying functions illustrated in FIGS. 1 or 2. Notations 33 and 34 refer to brackets welded or otherwise secured to the members 11', 17a and 35 to hold same in assembly with each other either at the end of the respective pipes 35 and 38 or on another superstructure (not shown).

In FIG. 4, a spray device 40 is provided which is applicable to the end of a pipe or hose to provide a fine spray of liquid particles therebeyond for a variety of purposes. A first cylindrical tube 41 is disposed outwardly of a second tube 42 to provide an annular volume 43 therebetween, into which volume a gas is introduced under pressure. Liquid is introduced to the interior volume 44 defined by the second tube 42 and is caused to flow through a porous plug 45 secured to the end of tube 42 and having a conical porous sidewall 46. A flanged portion 47 of plug 45 is clampingly engaged by the inside surface of the end face ofa threaded end cap 50 against a washer plate 48 which abuts the ends of inner tube or pipe 42. The plate 48 has a plurality of holes 49 extending in a circular array therethrough near the periphery of the plate. The holes 49 align with a plurality of holes 47 in the face portion of the cap 50, the latter holes being directed so as to direct gas from annular chamber 43 and holes 49 in washer 48 against the outer conical surface of porous member 45. The end of tube 41 is threaded at 41 and threads 52 provided on the inside surface of the sidewall 51 of cap 50 permit assembly of said cap with the end of tube 41 so as to clampingly engage the porous member 45 and the washer 48 together and against the end ofinner pipe 42.

In FIG. 5, a spraying device 53 applicable to the end of a pipe or hose is provided. The pipe may be defined by the conduit 54 or connected thereto by a coupling (not shown). A cylindrical ring 58 is welded or otherwise secured to the end of 54 and is externally threaded at 59 to receive the internal threads 61 of a cylindrical coupling 60 having an end wall 60 which, when member 60 is tightened against member 58, clampingly engages the flanged portion 47' extending from the conical sidewall 46 of a porous member 45' somewhat like the member 45 of FlG. 4.

To effect the spray-dispensing of liquid from the device 53 of FlG. 5, a smaller pipe or tube 56 is supported within the passageway 55 defined by pipe 54 and extends to and abuts the conical inside surface of member 45 as shown. Gas directed through the interior 57 of pipe 56 is ejected from the end thereof through the porous wall 46 near its apex and forces liquid flowed into said wall under pressure beyond the exterior surface of member 45 as an atomized spray of said liquid.

It is noted that the spraying devices of FIGS. 4 and are designed to permit the components to be easily assembled and disassembled. Welding or sintering may also be provided to more or less permanently affix certain of the components together. Suitable sealants or resilient washers may also be applied between certain of the mating surfaces to prevent leakage.

in FIG. 6, a simple spraying device 62 is provided in the form of an elongated box-shaped extrusion having top and bottom walls 63, 64 and sidewalls 65, 70 separated by a partition 66. Gas is introduced into a first chamber 68 defined by walls 65 and 66 while liquid to be dispensed is introduced into a second chamber 69 defined between the end wall 70 which is porous and the partition 66. A plurality of holes 67 in partition 66 permits gas from chamber 68 to be directed as a plurality of high-velocity jet streams through the chamber 69 so as to force liquid therein through the porous wall 70 to be dispensed therebeyond as a sheetlike spray or a plurality of closely spaced individual sprays of atomized particles of liquid. The device 62 of FIG. 6 may be made of an extrusion 'having a shape other than that illustrated such as a circular cylindrical wall separated by a partition therein provided as a single extrusion or as a plurality of semicylindrical extrusions which are welded or otherwise bonded together after the flat wall portions of each are properly drilled and aligned to provide the passageways 67. it is noted that the pressurized gas introduced into the passageways 15, 28, 38, 43, 55 and 68 may be preheated by a suitable heater of any conventional design to a high enough temperature to cause the liquid which it contacts and forces through or from the described porous members to become vaporized as it leaves the porous member.

in the operation of the apparatus described, a number of techniques may be employed to enhance the spraying or atomizing action or to otherwise control the material or materials being dispensed. Certain modifications thereto are therefore hereby proposed:

a. One or more ultrasonic transducers may be disposed in contact with the porous wall portion ofthe described conduit or plugs so as to vibrate same in the ultrasonic range (20 kc. or higher) at sufficient amplitude to provide a desired fine atomized spray or vapor of the liquid being dispensed. The ultrasonic transducer or transducers may also be coupled to the nonporous duct or wall portion of the duct containing a porous wall portion so as to vibrate said duct to effect improvement in flow of liquid through the porous wall and improvement in the atomization of vaporizing of said liquid beyond the porous wall.

b. The gas and/or liquids described may be intermittently pulsed in a manner to predeterminately control the flow, atomization or vaporization of the liquid.

. Vaporization ofliquid from the porous surfaces described may be effected by preheating the gas to be ejected as described to a temperature sufficient to vaporize the liquid through which it passes or which it picks up on the porous surface.

d. The porous conduit, wall portion or end plugs described may be made of a material having a high degree of wear resistance to erosion such as a sintered, porous ceramic or metal materials of high wear resistance. For example, said porous material may be made of sintered tungsten carbide, titanium carbide, silicon carbide, aluminum oxide, stainless steel, tungsten or other metals. The members may be fabricated of these materials provided in powder or particulate form or in filament or whisker form prior to sintering or welding of the particles together.

. Porous tubular members of the type shown in FIG. 1 may be fabricated by introducing particles of the abovedescribed materials into an extrusion press together with a suitable binding agent of the type used in conventional sintering and forcing said particles with binding agent through an annular extrusion orifice to form the desired shape while inductively or radiantly heating the extruded shape as it is fed through and/or from the extruder so as to properly sinter the particles together and burn off the binding agent to provide a porous walled extrusion. Composite extrusions of the type shown in FIG. 6 may be fabricated by predeterminately controlling the flow of nonporous metal or ceramic through an extrusion die and particles of metal or ceramic to be sintered to define a portion of the extrusion such as wall portion of FIG. 6. By predeterminately heating said sinterable portion of the extrusion as it is fed so as to sinter same and burn off the binding agent as described, unitary members of the type shown in FlG. 6 having porous and nonporous wall portions may be produced.

. In another technique for producing a conduit such as 17 of FIG. l for the extrusion shown in FlG. 6, a nonporous member may first be formed and all or a portion of its wall rendered porous by moving said member past one or more lasers operative to intermittently generate intense beams of light energy and direct same against the portion of the wall of the extrusion to be rendered porous. By properly pulsing the laser and controlling the relative speed between the extrusion and the laser, holes may be burned through the wall of the extrusion of predetermined size and spacing to provide the desired porous walled conduits.

lclaim:

l. Spraying apparatus comprising:

a. a first conduit,

b. a wall portion of said first conduit being made ofa porous material having passageways communicating between the inside and outside surfaces of said wall portion,

. a second conduit disposed adjacent to said first conduit,

. an opening in said second conduit,

e. means for introducing a liquid under pressure to said first conduit,

f. means for introducing a gas under pressure to said second conduit,

g. said opening in said second conduit being directed and disposed so as to direct said gas through the porous portion of the wall of said first conduit, said gas being under sufficient pressure to force liquid in the porous wall of said first conduit away from the exterior surface thereof as a spray or mist.

2. Apparatus in accordance with claim 1, said second conduit having a plurality of closely spaced holes extending through the wall portion thereof adjacent to said first conduit and each operative to direct a high-velocity stream of gas through said first conduit to force liquid from the porous wall of said first conduit.

3. Apparatus in accordance with claim 1, said second conduit extending through the interior of said first conduit, said porous material terminating at the end of said first conduit, said second conduit having its open end terminating against the inside face of said porous material at sufficient velocity to cause liquid flowed through the porous material from said first conduit to be dispensed from the outer surface of said porous material as finely divided particles of said liquid.

4. Apparatus in accordance with claim 1, including means for heating said gas to a high enough temperature prior to flowing said gas from said second conduit to cause the liquid of said first conduit to be come vaporized as it leaves the porous wall portion of said first conduit.

5. Fluid processing apparatus comprising:

a. a first conduit having opposite wall portions made of porous material,

b. a second conduit disposed adjacent to said first conduit,

0. an opening in said second conduit,

d. means for introducing a liquid under pressure to said first conduit,

e. means for introducing a gas under pressure to said second conduit,

f. means for directing high-velocity gas from said opening in said second conduit through the opposite porous wall portions of said first conduit to force liquid in said conduit through the porous wall thereof and to introduce said liquid as a finely divided spray beyond said first conduit.

6. Apparatus in accordance with claim 5 including means for heating said gas to a high enough temperature prior to flowing said gas from said second conduit to cause the liquid of said first conduit to become vaporized as it leaves the porous wall portion of said first conduit.

7. Spraying apparatus comprising:

a. a first conduit,

b. a wall portion of said first conduit being made of a porous material having passageways communicating between the inside and outside surfaces of said wall portion,

. a second conduit disposed adjacent to said first conduit,

. a plurality of holes in the wall of said second conduit,

. means for introducing a liquid under pressure to said first conduit, means for introducing a gas under pressure to said second conduit,

g. said plurality of holes in the wall of said second conduit being disposed so as to direct a plurality of high velocity jets of gas from said second conduit above the exterior surface of the porous wall portion of said first conduit with each jet of gas being operative to pick up and dispense a film of said liquid formed on the exterior surface of said first conduit as an extended sheetlike spray of particles of said liquid beyond said first conduit.

8. Apparatus in accordance with claim 6, said second conduit being disposed within said first conduit, and a porous member terminating the end of said first conduit and tapering inwardly therefrom, closure means at the end of said first conduit, a plurality of openings in said closure means extending around and peripheral of said porous member, said openings being directed so as to direct a plurality of high-velocity streams of gas over the surface of said porous member to lift liquid flowed to said surface and to generate finely divided particles of said liquid in the volume eyond the end of said porous member. 

1. Spraying apparatus comprising: a. a first conduit, b. a wall portion of said first conduit being made of a porous material having passageways communicating between the inside and outside surfaces of said wall portion, c. a second conduit disposed adjacent to said first conduit, d. an opening in said second conduit, e. means for introducing a liquid under pressure to said first conduit, f. means for introducing a gas under pressure to said second conduit, g. said opening in said second conduit being directed and disposed so as to direct said gas through the porous portion of the wall of said first conduit, said gas being under sufficient pressure to force liquid in the porous wall of said first conduit away from the exterior surface thereof as a spray or mist.
 2. Apparatus in accordance with claim 1, said second conduit having a plurality of closely spaced holes extending through the wall portion thereof adjacent to said first conduit and each operative to direct a high-velocity stream of gas through said first conduit to force liquid from the porous wall of said first conduit.
 3. Apparatus in accordance with claim 1, said second conduit extending through the interior of said first conduit, said porous material terminating at the end of said first conduit, said second conduit having its open end terminating against the inside face of said porous material at sufficient velocity to cause liquid flowed through the porous material from said first conduit to be dispensed from the outer surface of said porous material as finely divided particles of said liquid.
 4. Apparatus in accordance with claim 1, including means for heating said gas to a high enough temperature prior to flowing said gas from said second conduit to cause the liquid of said first conduit to be come vaporized as it leaves the porous wall portion of said first conduit.
 5. Fluid processing apparatus comprising: a. a first conduit having opposite wall portions made of porous material, b. a second conduit disposed adjacent to said first conduit, c. an opening in said second cOnduit, d. means for introducing a liquid under pressure to said first conduit, e. means for introducing a gas under pressure to said second conduit, f. means for directing high-velocity gas from said opening in said second conduit through the opposite porous wall portions of said first conduit to force liquid in said conduit through the porous wall thereof and to introduce said liquid as a finely divided spray beyond said first conduit.
 6. Apparatus in accordance with claim 5 including means for heating said gas to a high enough temperature prior to flowing said gas from said second conduit to cause the liquid of said first conduit to become vaporized as it leaves the porous wall portion of said first conduit.
 7. Spraying apparatus comprising: a. a first conduit, b. a wall portion of said first conduit being made of a porous material having passageways communicating between the inside and outside surfaces of said wall portion, c. a second conduit disposed adjacent to said first conduit, d. a plurality of holes in the wall of said second conduit, e. means for introducing a liquid under pressure to said first conduit, f. means for introducing a gas under pressure to said second conduit, g. said plurality of holes in the wall of said second conduit being disposed so as to direct a plurality of high velocity jets of gas from said second conduit above the exterior surface of the porous wall portion of said first conduit with each jet of gas being operative to pick up and dispense a film of said liquid formed on the exterior surface of said first conduit as an extended sheetlike spray of particles of said liquid beyond said first conduit.
 8. Apparatus in accordance with claim 6, said second conduit being disposed within said first conduit, and a porous member terminating the end of said first conduit and tapering inwardly therefrom, closure means at the end of said first conduit, a plurality of openings in said closure means extending around and peripheral of said porous member, said openings being directed so as to direct a plurality of high-velocity streams of gas over the surface of said porous member to lift liquid flowed to said surface and to generate finely divided particles of said liquid in the volume beyond the end of said porous member. 